Illinois 146 Widening


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Illinois 146 Widening


Thank you for visiting the Illinois 146 widening and roundabout project page. The Illinois Department of Transportation is in the planning and early design stages for this roadway improvement. The project will take place on the east side of Vienna and consists of widening the route to three lanes: two travel lanes and a two-way left turn lane.

The widening will begin west of Vienna City Park and continue to the east to the intersection of Illinois 146 and Red Bud Lane. At the intersection of Red Bud Lane, IDOT plans to widen and resurface Illinois 146 from Vienna City Park to a modern roundabout. In addition to the widening and roundabout, there will be a 10-foot wide shared-use path that will tie into the Tunnel Hill State Trail and end at the roundabout. The road will be resurfaced beginning east of the intersection with U.S. 45 and ending at the ramps for eastbound Interstate 24.

There are two separate projects scheduled for Illinois 146 inside these project limits. This page provides the preliminary plans on the Illinois 146 widening project. Another project replaces the bridge over Little Cache Creek and construction on that bridge will begin in late summer 2021 and extend through 2022.Construction on the widening project will begin spring 2023 and is estimated to be completed within the year.

In the early stages of the design process, there were different options considered for the project. For example, one option looked at widening on both sides of the road and installing the trail on the left side of Illinois 146. Another option consisted of widening on the right side and installing the trail on the right side. The option that was chosen has the lane widening on the left side and two different trail offsets, depending on the available right –of way. This option was selected because it had the smallest right-of-way impact and allows for the least amount of traffic impact during construction, and it had smaller utility impacts of the other scenarios.

Please explore the project page for further information regarding the project. There are exhibits that include aerial renderings of the completed project, a simulation of the proposed roundabout, proposed typical sections of the road, and a safety analysis of the existing road. After reviewing the material, please fill out a comment form and return it to the department by May 21.

Questions about the project can be directed to:

Carrie Nelsen
District 9 Program Development Engineer
Phone number: (618) 549-2171 ext. 280

Note: IDOT projects typically have three distinct phases. Phase I (or the project Study) consists of developing the project scope, environmental studies and preliminary design of a project. Phase II (Design) consists of refining the design to develop contract plans and land acquisition. Phase III (Construction) consists of the actual construction of the project.